Magnetic characterization of nanocrystalline Fe14Nd2B1 alloy during melt spinning and subsequent annealing

The magnetic characterization of amorphous/nanocrystalline Fe14Nd2B1 alloy during melt spinning and subsequent annealing was the goal of this study. The melt spinning process was done at different wheel speeds in the range of 20 to 40 m s−1. To achieving the desired microstructure, the annealing process was also done in melt spun ribbons at temperature range of 500 to 700 °C for different periods of time. The melt spun and annealed samples were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), dispersive X-ray spectrometry (EDS), differential scanning calorimetry (DSC) and vibrating scanning magnetometer (VSM). According to achieved results, the microstructure of melt spun ribbons were combination of Nd2Fe14B, Fe-α and amorphous phases with the coercivity and saturation of magnetization in the range of 11.2-125.6 kA/m and 65-120 A m2/kg, respectively. By annealing the ribbons, the coercivity and saturation of magnetization increased and decreased, respectively. The highest values of coercivity (752 kA/m) and stored magnetic energy (about 267.68 kJ/m3) were achieved in annealed sample at 600 °C for 6 h.